On Tue, Feb 8, 2011 at 9:06 AM, Frederick Cheung <[email protected] > wrote:
> > On Feb 8, 2:44 pm, David Kahn <[email protected]> wrote: > > I have this line, where the input variables in the array can come in any > > form --- string, integer, fixnum, float (ps, I know that sales_price as a > > currency should really be BigDecimal or the like on instantiation, this > is > > just to illustrate my question): > > > > [quantity, sales_price].each { |multiplicand| multiplicand = > > BigDecimal.new(multiplicand.to_s) if multiplicand.class != BigDecimal} > > > [snip] > > All each does is iterate over a collection, yielding to the block. > when you do multiplicand = blah, you are just setting the local > variable multiplicand to point at some new object - you're not > mutating the actual object. > I see, I guess I got confused as I use ActiveRecord so much and within a each block, by setting values and calling save it of course saves the object. Is there a way to achieve what I am presenting, though, passing a batch of variables and having them operated on and changed? This situation: (rdb:1) v1 = 1 1 (rdb:1) v2 = 2 2 (rdb:1) v3 = 3 3 (rdb:1) arr = [v1,v2,v3] [1, 2, 3] (rdb:1) arr = arr.map{|i| i = i + 1} [2, 3, 4] However what I would want is to see the variable values changed but they are not: (rdb:1) v1 1 (rdb:1) v2 2 Excuse my ingenuity, but I am trying to understand... if I have an array of variables it seems that when the array is created, the elements which were variables are substituted by values, and there is no reference: (rdb:1) arr = [v1,v2,v3] [1, 2, 3] (rdb:1) v1 1 (rdb:1) arr[0]=5 5 (rdb:1) v1 1 This must sound like kindergarten but apparently I have been working albeit successfully under some very false premises. > > Fred > > -- > You received this message because you are subscribed to the Google Groups > "Ruby on Rails: Talk" group. > To post to this group, send email to [email protected]. > To unsubscribe from this group, send email to > [email protected]. > For more options, visit this group at > http://groups.google.com/group/rubyonrails-talk?hl=en. > > -- You received this message because you are subscribed to the Google Groups "Ruby on Rails: Talk" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/rubyonrails-talk?hl=en.
